This invention relates to a flange structure. More particularly, this invention relates to a flange structure utilized to replace damaged flanges such as flanges utilized to connect conduits.
At the present time, it is common practice to connect conduits with a flange on each conduit together with means for securing the flanges to each other. Automobile exhaust systems are an example of a system of connected conduits which utilize connecting flanges. These exhaust systems include a plurality of connected modules such as pipes, a catalytic converter and an exhaust muffler. The modules are provided with flanges to effect connection with an adjacently positioned module such as with bolts extending through the flanges which are secured with nuts. As automobile exhaust systems are operated in a corrosive environment, particularly in winter conditions when the system is exposed to salt, moisture and sand, portions of the system, including the flanges become severely corroded to the extent that they become detached from an adjacent flange. When this condition occurs, repairs must be made so that connection of modules in the exhaust system can be reestablished in order to permit the system to function properly. Oftentimes, it is not possible to repair the flange, thereby necessitating replacement of the entire module to which the flange is attached. This damaged flange condition also requires unnecessary expense since the remaining portion of the module, such as the exhaust muffler or catalytic converter can be in acceptable working order.
It has been proposed in U.S. Pat. No. 4,519,639 to provide a segmented hinged flange for a conduit. The flange segments are formed from laminated metal sheets which interleave with metal sheets of an adjacently positioned segment at the juncture points between segments. The segments surround a conduit to be attached to an adjacent conduit. The segments are joined by bolts extending through the laminated metal sheets at the juncture points. The joining bolts extend beyond the thickness of the segments and thus increase the effective thickness of the flange. This, in turn, limits the use of the flange to a relatively large volume of space to accommodate both the flange thickness and the added thickness of the added bolts. In addition, the interior size of the flange opening is not adjustable so that a wide size range of flange structures must be provided to accommodate a wide variety of conduit sizes.
U.S. Pat. No. 5,203,593 discloses a flexible exhaust coupling utilizing resilient annular gasket means designed to permit related movement between adjacent joined conduits.
U.S. Pat. No. 5,228,726 discloses an exhaust system clamp having flared flanges for connecting two conduits to permit axial expansion of the conduits during use.
U.S. Pat. No. Des. 263,415 discloses a design for a pipe coupling flange. It would be desirable to provide a flange structure which can be attached to a conduit to accommodate conduits of varying sizes. It would also be desirable to provide such a flange structure including means for attaching the flange structure to a conduit, which occupies a minimum volume. In addition, it would be desirable to provide such a flange structure which can be secured to a slightly damaged conduit surface with a flared end while minimizing or preventing damage to the conduit.